&}FERRO. Technical Information GL18. Glaze Catalogue. Where innovation delivers performance. Performance Colors and Glass

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1 &}FERRO Where innovation delivers performance Technical Information GL18 Performance Colors and Glass Performance Colors & Glass Glaze Catalogue In this Technical Information bulletin we are introducing a selection of glazes for earthenware, tableware and art ceramics, stove tiles and stoneware. Additionally, several useful specialty frits for glaze corrections are listed. A catalogue with the most common glaze defects is provided as well. At the end of this bulletin, a table with the glaze properties is given. The here mentioned glazes and frits resemble only a small selection of our complete product range. Please let us know if your desired glaze is not included. For assistance in selecting and adapting your glazes, please call our technical service department. Content Transparent glazes, lead free p. 2 Transparent glazes, lead containing p. 4 Matt glazes p. 5 Opaque glazes p. 5 Effect and oversaturation glazes p. 6 Stoneware glazes p. 8 Stove Tiles p 10 Fashionable colors for superior designs p. 10 Stylish design in up-to-date combinations p. 11 Conventional colors with a modern touch p.13 Up-to-date designs show the latest trends p. 14 Traditional colors with modern appearance p. 18 Special frits p. 19 Glaze defects p. 20 Glaze properties p. 22

2 page 2/22 Transparent Glazes, Lead Free VTR F transparent, glossy temperature range: 1040 to 1100 C The glaze VTR F is a universally suitable glaze for earthenware, tableware and art ceramics. It develops colors well, including pink stains (CaSnSiCr) and inclusion pigments, also with coloring oxides. Granulated glazes and stains can be stirred in. Interesting crystalline eliminations can be achieved with the addition of (0.6 to 2.0 g for 100 g of glaze). VTR 166 transparent, glossy temperature range: 1040 to 1100 C The glaze VTR 166 is an economic alternative to the glaze VTR F, but more viscous. It shows a good development of colors as well with almost all stains and inclusion pigments, but only limited with cobalt aluminate blue and not with pink (CaSnSiCr). Specialty: together with the glaze F or the frit , good results are obtained for the inclusion pigments and VTR 320 transparent, glossy especially low temperature range: 920 to 980 C The color development of this glaze is good, although at 920 C it reaches its limits. The glaze VTR 320 is only partially suitable for the inclusion pigments and Pink stains (CaSnSiCr) turn brown.

3 page 3/22 VTR 102 transparent, glossy temperature range: 980 to 1070 C The glaze VTR 102 is a soft glaze for earthenware, tableware and art ceramics. It can be blended especially well with the glaze VTR 166, with a recommended ratio of 30:70. The color development is excellent with all stains, especially in the low temperature range. VTR 102 is recommended for pink stains (CaSnSiCr). It is not suitable for CoAl blue and has only limited suitability for cobalt silicate blue and the inclusion pigments and VTR TM transparent, glossy temperature range: 1060 to 1100 C The glaze VTR TM is the best choice for pink stains. It is suitable for earthenware, tableware and stove tiles. The color development of stains is good, but not with coloring oxides. Specialty: The addition of 6 to 8 g alumina to 100 g of glaze results in a matt glaze that may be colored with all kinds of stains.

4 page 4/22 Transparent Glazes, Lead Containing VTR F transparent, glossy PbO 39 weight % temperature range: 950 to 1040 C The glaze VTR F isa typical glaze for pink stains. It can be easily colored with stains, especially with pink (CaSnSiCr). VTR F is a perfect choice in underglaze painting. VTR 17 transparent, glossy PbO 43 weight % temperature range: 950 to 1040 C The glaze VTR 17 is usable for art ceramics and stove tiles, especially for raw bodies. It may be colored with stains and oxides, but not with pink (CaSnSiCr). The color development in a gas kiln is better than in the electrical kiln. VTR 39 transparent, glossy PbO 2 weight % temperature range: 980 to 1020 C The glaze VTR 39 is suitable for earthenware and art ceramics. It may be colored with stains, except with pink. VTR F transparent, glossy PbO 14 weight % temperature range: 1040 to 1080 C The glaze VTR F is universally suitable transparent glaze for earthenware, art ceramics and stove tiles. It is especially suitable for raw bodies in gas kilns. With stains and coloring oxides it shows a good color development. Granulated glazes and stains may be stirred in.

5 page 5/22 Matt Glazes VTR F matt, colorless, lead free temperature range: 1020 to 1100 C The glaze F is a universally suitable matt glaze for earthenware, tableware, art ceramics and stove tiles. It develops color stains nicely, even pink (CaSnSiCr) and all inclusion pigments. Additionally, granulated glazes and stains may be used. In the upper temperature range (1080 to 1120 C) the surface is silk-matt. Specialty: the addition of 15 % zircon silicate results in a smooth, white matt surface. VTR TM colorless, silk-matt, lead free temperature range: 1020 to 1080 C The glaze TM is a matt basic glaze for effect-building components, suitable for earthenware, art ceramics and stove tiles. It is perfect for color stains. Interesting oversaturation effects are created by the addition of all kinds of granulated glazes, stains and frits. These effects are enhanced by additions of , or Opaque Glazes VBC 13 opaque, glossy, lead free temperature range: 980 to 1060 C The glaze VBC 13 is suitable for earthenware, tableware and art ceramics. It fires well on raw bodies in gas kilns. At firing temperatures higher than 1020 C it may be used for majolica painting.

6 page 6/22 Effect and Oversaturation Glazes VBC TM beige, silk-matt, low degree of crystalline eliminations, lead free temperature range: 1020 to 1140 C The glaze VBC TM is ideal for earthenware, stove tiles and art ceramics. It can be colored with stains and is suitable for granulates. The addition of and enhances the effects. VBC TF beige, slight silk-matt effects, lead free temperature range: 1020 to 1080 C The glaze VBC TF is a versatile earthenware glaze, ideal also for stove tiles. The coloring with stains is limited, but the coloring with frits and oxides is possible. The addition of all kinds of granitis enhances the oversaturation effects , and/or also show interesting effects. Specialty: the use of a base glaze TF, colored with stains, together with a top glaze of VTR 166 with F or of F, also colored with oxides, creates a very interesting appearance. Example 1 Base glaze: TF Top glaze: VTR TF The red is very similar to a selenium red, but this special effect cannot be achieved with a selenium glaze. Example 2 Base glaze: Top glaze: TF F The base glaze may preferably be colored dark. The top glaze may be colored as pleases, but preferentially in contrasting colors to the base glaze. Fine or strong effects are created when using different layer thicknesses of base and/or top glaze. They can be adjusted individually according to demand.

7 page 7/22 VBC TM opaque, silk-matt, lead free temperature range: 1000 to 1080 C This is a silky-elegant effect glaze for earthenware, stove tiles and art ceramics. The glaze is suitable for creating pastel shades by the use of color stains. A surface refinement is achieved by the addition of 2 % Granitis enhance the eliminations significantly. Example for a very elegant surface: TM zircon silicate 8 Stir into the glaze slip: GY GY 15

8 page 8/22 Stoneware Glazes VTR E transparent, glossy, lead free temperature range: normal firing 1190 to 1250 C, fast firing 1260 C (4 hours) The glaze VTR E is a versatile stoneware glaze, easy to color with stains, with high brilliance and perfectly suitable for tableware. The addition of granitis, like , results in nice effects. Blended with 10 % aluminium oxide, a colorless matt glaze is obtained, whereas 15 % zircon silicate create a glossy white glaze. Specialty: the addition of 5 to 15 % of the frit FTR F lower the melting point of the glaze VTR F to 1140 to 1180 C. Crystals The glaze E as base glaze in combination with a top glaze and with develops crystals of different sizes. Example: Base glaze: E, with zircon and stains Top glaze: kaolin lithium carbonate 52 zinc oxide, lead free 52 alumina 31 FTR M 175 FTR M 484 When adding 1 to 2 % of to the top glaze, interesting dissolutions and crystalline effects are created. The addition of 3 to 5 % of to the top glaze cause the formation of crystals. The size and intensity of the crystals can be influenced by the quantity of added to the top glaze and/or by the layer thickness of the top glaze. Depending on the body and on the firing conditions, the effects have to be adjusted individually.

9 page 9/22 VTRS 115 transparent, glossy, lead free temperature range: 1150 to 1200 C The glaze VTRS 115 is a basic glaze for stoneware, for fired and for raw bodies. It is well suitable for ZrSiV and ZrSiPr stains and common inclusion pigments. l ~ VTRS 115 with raw material mixture and FTR M temperature range: 1150 to 1220 C Different blending ratios show a fired surface from matt to glossy. Slight effects may be combined with all kinds of stains and develop nicely in the glossy version up to 1180 C. Examples: glossy: VTRS FTR M 17 raw material mixture 58 matt: VTRS FTR M 23 raw material mixture 62 strongly matt: VTRS FTR M 10 raw material mixture 85 Raw material mixture for the glaze VTRS 115: zinc oxide, lead free 123 silica 148 kaolin 173 calc spar 210 sodium feldspar 247 The addition of 2 % to the blends shows slight crystalline eliminations in the case of the glossy version and interesting eliminations in the matt versions. The exchange of the more viscous frit with the frit is possible. The eliminations are then decreased or totally avoided. The firing temperature may then be increased to 1250 C.

10 page 10/22 Stove Tiles Fashionable colors for superior designs Variation 1: Brown wiped Underglaze Decorating glaze F 100, F 100,0 ZrSiO4 2,0 ZrSiO4 2, , , , , , , ,0 spray evenly sprinkle thickly and wipe with a sponge immediately Variation 2: Red wiped Underglaze Decorating glaze F 100, F 100, , , , , ,0 spray evenly sprinkle thickly and wipe with a sponge immediately Variation 3: Dark brown wiped Underglaze Decorating glaze F 100, F 100, , , , , , , ,0 spray evenly sprinkle thickly and wipe with a sponge immediately Variation 4: Dark red wiped Underglaze Decorating glaze F 100, F 100, , , , ,0 spray evenly sprinkle thickly and wipe with a sponge immediately

11 page 11/22 Stylish design in up-to-date combinations Orange in combination with chocolate brown Orange Underglaze; evenly sprayed F 100, ,0 SnO2 5,0 ZnO 1 7,0 Stippling glaze 1 Stippling glaze F 100,0 VTR , , , ,0 Chocolate brown Underglaze; evenly sprayed F 100,0 ZrSiO4 2, , , , ,0 Stippling glaze 1 Stippling glaze F 100,0 VTR , , ,0 Yellow - orange in combination with sand Yellow - orange Glaze, evenly sprayed TM 100, , , , , only stirred in Sand Underglaze; evenly Decorating glaze; sprinkeled FCM , TM 100, , , ,0

12 page 12/22 Rosé in combination with dark brown Rosé underglaze Rosé stippling glaze F ,0 1, F ,0 2,0 2,0 1,0 Dark brown Underglaze, evenly sprayed F 100, , ,0 Stippling glaze 1 Stippling glaze F 100,0 VTR ,0 ZrSiO4 2, , , , ,0 Sunny yellow in combination with blue Sunny yellow underglaze Sunny yellow stippling glaze F 100, F 100, , ,0 Blue Underglaze, evenly sprayed Stippling glaze F 100, F 100, , , ,0 Stippling glaze 2 Stippling glaze F 100,0 VTR , ,0

13 page 13/22 Conventional colors with a modern touch Variation 1 Black - blue marbled Underglaze, evenly sprayed F 100, ,0 Stippling glaze 1 Stippling glaze F 100, F 100, , ,0 CK ,4 Variation 2 Black - grey marbled Underglaze, evenly sprayed F 100, ,0 Stippling glaze 1 Stippling glaze F 100, F 100, , ,0

14 page 14/22 Up-to-date designs show the latest trends Combination A , , , GR 2, F 100, , , GR 4, GR 4,0 Combination B ZrSiO4 10, , , , GY 5, GY 5,0 1 H phrase F 100,0 ZrSiO4 5, , , , GR 1 2,0

15 page 15/22 Combination C ZrSiO4 5, , , , GY 5, GY 5, F 100, , GY 5, GY 5,0 Combination D ZrSiO4 5, , , , GY 5, GY 5, , GY 5, GY 5,0

16 page 16/22 Combination E , , GY 5, GY 5, , , , GY 5, GY 5,0 Combination F , , GR 4, GR 4, , , , GR 2,0

17 page 17/22 Combination G FCM , GR 2, , GY 5, GY 5,0 Combination H GR 2,0 CK , , , GR 4, GR 4,0

18 page 18/22 Traditional colors with modern appearance F 100,0 Iron oxide 4, F 100,0 1 Copper oxide 3,0 Iron oxide 1, F 100,0 1 Copper oxide 4,0 Iron oxide 1, F 100,0 Iron oxide 4,0 2 Manganese oxide 2, F 100,0 Iron oxide 4,0 Manganese oxide 2 3, F 100,0 1 Copper oxide 4,0 Iron oxide 1,0 3 Cobalt oxide 0, F 100,0 3 Cobalt oxide 2, F 100,0 Manganese oxide 2 4,0 1 GHS symbol 09, H phrase GHS symbol 07, H phrases 302, GHS symbol 08, H phrases 334, 412

19 page 19/22 Special Frits FTR lead free; frit with a c.t.e. of 40 (*10-7 /K); for correction of hair cracks FTR lead free; an alternative to lead frits (up to 30 % lead); in combination with kaolin and silica suitable as a top coat for traditional firing; for earthenware and tableware FTR lead free; lithium frit; for correction of surface tension; causes effects and crystals; for earthenware and stoneware FTR lead free; together with the frit FTR used as a base for effect glazes; for earthenware FTR lead free; ZnBa frit, base for matt elimination glazes; for earthenware FTR lead free; base for calcium containing glazes; for earthenware and tableware FTR lead free; barium frit; to be used instead of barium silicate; causes effects; for earthenware and stoneware FTR lead mono silicate FTR lead containing frit with 21.0 weight-% lead; zinc base for silk-matt effect glazes CE lead free; barium frit 1 GHS symbol 07, 08, 09, H phrases 302, 332, 360Df, 373, 410 ~ \' [ })

20 page 20/22 Glaze Defects Why do glaze defects occur? In the following chapter the most common defects and hints to avoid them are given. Overfiring or Underfiring The most common reasons for glaze defects are underfiring or overfiring. Underfiring causes a dry, scratchy surface. Often this can be cured by a second firing at a higher temperature. Overfiring causes the glaze to flow. The glaze is then thinner at the top and thicker at the bottom. Sometimes it even drops from the body. Strongly overfired ceramics may also show pinholes and pitting, if the glaze reaches its evaporation temperature. Overfiring cannot be corrected. Differing Coefficients of Thermal Expansion The body and the glaze may have very different coefficients of thermal expansion (c.t.e.). If the c.t.e. of the glaze is too high, it might lead to the formation of cracks. If it is too low, it might cause chipping. A too low c.t.e. might be adjusted by adding 2 to 7 % of the frit If the c.t.e. is too high, 5 to 10 % of the frit might correct this. Application Problems and Adhesion of the Unfired Glaze Wrong application of the glaze is the reason for several glaze defects. A too thin application might result in rough surfaces and also influence the glaze color. A glaze application that is too thick promotes running and blistering. Uneven application causes stains and stripes, in the color as well as in the surface structure. Mistakes during application also influence the adhesion of the glaze to the body. The body must be clean and dry before the glaze is applied. If a second glaze should be applied on top, the first must be dried completely before doing so. Adhesion problems often cause a rolling off of the glaze. Adhesion problems might be avoided by testing the glaze slip before application. The weight per litre and the viscosity should be measured. To keep the glaze slip from settling, a suspending agent should be used. When glazing raw bodies, adhesive should always be used. Hair Cracks, Chipping and Peeling Hair crack formation means the formation of a network of finer or thicker cracks in the fired glaze, sometimes directly after firing, sometimes later. Except in some special glazes, the formation of cracks is not desired. There are several reasons for the formation of hair cracks. Normally cracks are occuring if the coefficient of thermal expansion of the glaze is too high. Due to the tension during cooling the glaze is crazing. The addition of the frit and/or kaolin might help. Cracks can also be caused by thermal shock due to a too fast temperature change. Longer soaking times and slower cooling help to avoid these cracks. A thinner layer of glaze or the addition of silica to the body are also advantageous. In case of porous bodies with unglazed areas, moisture might be absorbed, which may lead to an expansion of the body. Then the body should be fired at a higher temperature or more calc spar should be added to the body. Peeling and chipping is caused by a glaze c.t.e. that is too low. In this case the frit should be added to the glaze. Firing at lower temperatures and faster cooling could help. Perhaps also the feldspar and/or clay content of the body may be increased. Very important is the formation of a good intermediate layer, that means the adhesion of the glaze to the body. A good intermediate layer is able to equalize the tension between glaze and body. Longer firing cycles and a sufficient soaking time enhance the formation of the intermediate layer. Rolling off or Contraction of the Glaze after Firing When rolling off or contracting, the glaze leaves empty areas on the body after firing. Rolling off occurs if the glaze is not sticking to the body correctly. This might be the case if the body was not completely free of grease, dirt or moisture, or if the surface of the body is too smooth. Also a too thick layer of glaze can cause adhesion problems. Sometimes a glaze that is milled too fine can be the reason for rolling off. Rolling off also occurs if the raw glaze was not dried long enough. Too much opacifier may also lead to rolling off. Matt glazes with a high content of clay tend to rolling off, like too viscous glazes do.

21 page 21/22 If the surface tension is too high, the glazes might contract to droplets. This can be cured by additions of lithium, alkali or lead, which lower the surface tension. Blistering and Pinholes Blisters and pinholes are often formed by evaporating gas from the body or from the glaze while melting during the firing. In most cases the outgassing process leaves enough time for the glaze to flow back and form an even surface. If there is too much gas or the glaze is too viscous, the glaze might solidify although the gas has not evaporated completely. After firing, blisters and pinholes remain. Outgassing may have different reasons. Air in the body is often already formed during processing or due to the degradation of finished body material. In order to reduce air bubbles in the body, opening materials can be used. In the glaze, the formation of blisters is enhanced by too thick glaze layers or too high surface tension or viscosity. Mistakes during firing also increase the formation of blisters: too high temperature, a reductive kiln atmosphere at the beginning, too short firing cycles or too short soaking times. The kiln should be well ventilated at all times. Matt Stains, Glossy Areas and Discolorations One can distinguish between matt areas in a glossy glaze and glossy areas in a matt glaze. Additionally, discolorations or traces on fired pieces may occur. There are several reasons for matt stains. Among them are inhomogenious glaze applications or too low firing temperatures. The evaporation of fluxes, e.g. lead, during firing leaves no damage if the ventilation flaps of the kiln are left open. If there is excess water during heating, a good ventilation also helps. Glossy areas often are caused by too thin glaze layers or temperatures that are too high. The kiln atmosphere may be improved by sufficient air supply while heating and slow cooling. Discolorations often are formed by evaporated metal oxides, which were added to the glaze in pure form or as part of a color stain, e.g. chromium, copper or cobalt oxide. If the evaporation is very high without proper ventilation, even tiny crystals may occur. Only a sufficient ventilation of the kiln may solve the problem.

22 page 22/22 Glaze Properties Product no. Type % PbO C.T.E. [10-7 /K] Tableware/ eartheware Tableware/ stoneware Art ceramics/ stove tiles glossy matt Firing temperature C VTR F transparent glaze 0 61 x x x VTR 166 transparent glaze 0 56 x x x VTR 320 transparent glaze 0 62 x x VTR 102 transparent glaze 0 64 x x x VTR TM transparent glaze 0 60 x x x VTR F transparent glaze x x x VTR F transparent glaze x x VTR 17 transparent glaze x x VTR 39 transparent glaze 2 60 x x x VTR F matt glaze 0 57 x x x VTR TM matt glaze 0 62 x x x FCM matt glaze x x VBC opaque glaze 0 55 x x VBC 13 opaque glaze 0 58 x x x VBC TM effect glaze 0 62 x x x VBC TF effect glaze 0 65 x x x VBC TM 1 effect glaze 0 58 x x x VTR E stoneware glaze 0 59 x x VTRS 115 stoneware glaze 0 66 x x GHS symbol 09, H phrase 411 Limitation of Warranty and Liability Ferro believes that the information contained in this document is accurate at the time of its publication. Ferro makes no warranty with respect to the information contained in this document. The information in this document is not a product specification, either in whole or in part. Your use of the information contained in this document and your purchase and use of this Ferro product are at your sole discretion. Downstream users are responsible for determination of the suitability of this product and for testing in specific applications. Nothing in this document shall be construed as a license for use that infringes upon any property rights of any third party. Please refer to the Safety Data Sheet (SDS) for safe use, handling and disposal information. All sales by Ferro to you are subject to Ferro s Terms and Conditions of Sale, as amended from time to time and available at In the event this document conflicts with Ferro s Terms and Conditions of Sale, Ferro s Terms and Conditions of Sale shall control. FERRO GmbH I Gutleutstrasse 215 I D Frankfurt/Main Germany page 22 of 22 P F E info-pcg@ferro.com W ferro.com GL18 09, 2017